I'll add my $.02 for what it's worth. First by definition it was an accident, as has already been said a couple of times. It was unintentional, therefore accidental. As has also been said, that does not mean it was not negligent. It was negligent. We do not need to have all the details. There is no acceptable reason to have a loaded, unholstered weapon being passed around in this situation. There is no acceptable reason for the discharge of this weapon. The responsibility for all of this is on the owner of the weapon.
Training, experience, licensing are not the issue. This man violated the fundamental rules of carrying and handling a weapon. Carrying a weapon brings with it huge responsibility. " I didn't mean to," is of little consequence here. Tell that to the Pastor and his congregation. I understand we are all capable of doing something stupid, but when it comes to handling weapons we all have to do things right. Cooper's, "not me, not today" is a mantra we should all embrace IMO.